Field-induced phenomena in ferromagnetic superconductors UCoGe and URhGe

青木 大*; Taupin, M.*; Paulsen, C.*; Hardy, F.*; Taufour, V.*; 小手川 恒*; Hassinger, E.*; Malone, L.*; 松田 達磨; 三宅 厚志*; et al.

Journal of the Physical Society of Japan, 81(Suppl.B), p.SB002_1 - SB002_6, 2012/12

https://doi.org/10.1143/JPSJS.81SB.SB002

We review our recent studies on ferromagnetic superconductors, UGe2, URhGe, and UCoGe. We focus on experimental results of URhGe and UCoGe in which the superconductivity occurs already at ambient pressure. The huge upper critical field on UCoGe for the field along the hard magnetization axis (-axis) is confirmed by the AC susceptibility measurements by the fine tuning of field angle. Contrary to the huge along the hard-magnetization axis, along the easy-magnetization axis (-axis) is relatively small in value. However, the initial slope of , namely / (0) both in UCoGe and in URhGe indicates the large value, which can be explained by the magnetic domain effect detected in the magnetization measurements. The specific heat measurements using a high quality single crystal of UCoGe demonstrate the bulk superconductivity, which is extended under magnetic field for the field along -axis.

HRB-22 capsule irradiation test for HTGR fuel; JAERI/USDOE collaborative irradiation test

湊 和生; 沢 和弘; 福田 幸朔; Baldwin, C. A.*; Gabbard, W. A.*; O.F.Kimball*; Malone, C. M.*; F.C.Montgomery*; B.F.Myers*; N.H.Packan*

JAERI-Research 98-021, 187 Pages, 1998/03

JAERI-Research-98-021.pdf:13.23MB

日米高温ガス炉燃料共同照射試験として、日本の燃料コンパクトを米国オークリッジ国立研究所のHFIR炉で照射し、引き続き照射後試験を行った。本報告書では、(1)被覆燃料粒子を含む燃料コンパクトの照射前特性評価、(2)照射条件及び被覆粒子燃料の照射健全性の指標となる照射中の核分裂ガス放出、(3)外観検査、寸法検査、断面組織観察、及び線測定などの照射後試験、並びに(4)事故時条件における燃料の健全性及び核分裂生成物の放出挙動を調べるための照射済み燃料を用いた1600~1800Cにおける事故時挙動試験について記述した。